我使用的是bootstrap 4滑块。当引导程序滑块中的第一个项目处于活动状态时，我想更改主体的背景颜色。如果任何其他项目处于活动状态，则身体颜色将正常。在此处输入图像描述
.carousel-item{ width:100%; height:400px; background-color:red; text-align:center; line-height:400px; font-size:100px; color:#fff;}<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.2/js/bootstrap.min.js"></script>
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.2/css/bootstrap.min.css" rel="stylesheet"/>
<body>
<div id="demo" class="carousel slide" data-ride="carousel">
<!-- Indicators -->
<ul class="carousel-indicators">
<li data-target="#demo" data-slide-to="0" class="active"></li>
<li data-target="#demo" data-slide-to="1"></li>
<li data-target="#demo" data-slide-to="2"></li>
</ul>
<!-- The slideshow -->
<div class="carousel-inner">
<div class="carousel-item active"> 1 </div>
<div class="carousel-item"> 2 </div>
<div class="carousel-item"> 3 </div>
</div>
<!-- Left and right controls -->
<a class="carousel-control-prev" href="#demo" data-slide="prev"> <span class="carousel-control-prev-icon"></span> </a> <a class="carousel-control-next" href="#demo" data-slide="next"> <span class="carousel-control-next-icon"></span> </a> </div>
</body>使用转盘回调
$('#demo').on('slide.bs.carousel', function (e) {
if(!e.to){
//set body bgcolor
}else{
//remove body bgcolor
}
});
您可以在此处找到文档：https://getbootstrap.com/docs/4.0/components/carousel/#events